Field of Invention
The present invention relates to an oil supply system that securely supplies a low pressure portion for lubricating a component and a high pressure portion for operating elements a clutch and a brake with oil.
Description of Related Art
Generally, because an engine of an electric vehicle stops its operating during a low speed condition or a stop condition, a motorized hydraulic pump is provided in the electric vehicle instead of a mechanical hydraulic pump.
And, a hybrid vehicle can use a mechanical hydraulic pump and a motorized hydraulic pump, and there is a document as a conventional art, Korean patent application No. 10-2008-0123014 that describes a mechanical hydraulic pump and a hydraulic pump.
A motorized hydraulic pump is gradually used instead of a mechanical hydraulic pump, and when two motorized hydraulic pumps are used in a vehicle, one is used to supply a low pressure portion with oil and the other is used to supply a high pressure portion with oil.
Here, the low pressure portion uses low pressure oil to lubricate components and the high pressure portion uses high pressure oil to operate elements such as a clutch and a brake.
Meanwhile, while two hydraulic pumps are used to supply the low pressure portion and the high pressure portion with oil, if a pump for a low pressure oil or a pump for a high pressure oil cannot be operated, the oil cannot securely supplied to the low pressure portion or the high pressure portion.
The information disclosed in this Background section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.